Tag Archives: Enduron

Weir Minerals wins large comminution order from Nigeria iron ore mine

Two of the largest screens built by Weir Minerals Africa are being designed and manufactured in South Africa as part of a process solution for an iron ore mine in Nigeria.

According to Tiisetso Masekwameng, General Manager Comminution at Weir Minerals Africa, the flowsheet accepted by the customer includes equipment for screening, washing, and grinding supplied by Weir Minerals.

“Within our scope of work are the two largest Enduron® double-deck banana screens built by Weir Minerals,” Masekwameng says. “This is made possible by the depth of design expertise in our Separation Technology Group, an eight-strong team conducting research and development.”

Steven Hunter, Separation Technology Group Leader at Weir Minerals Africa, says the two 51 t Enduron double-deck banana (DBHG 43/97) screens (one pictured) for this project were built upon the designs of the existing Weir Minerals screens range. These large machines measure 4.3 m wide and 9.7 m long and can process 1,750 t/h.

“The customer’s production requirements demanded this considerable size, so we optimised the design by minimising mass without compromising structural integrity,” Hunter says. “We conducted extensive finite element analysis on the whole machine but focused on the main structural elements, ensuring that the units were fit-for-purpose while still being light enough to be driven by the exciters.”

The size of the units still demanded the design and manufacture of Weir Minerals Africa’s largest exciter yet – the Enduron LTX 10. With 120 t of excitation force (at maximum setting), these units will drive the screens at a stroke of 9.4 mm and a gravitational force of 4.6 G.

Hunter said the screens are ready to be fitted with Weir’s IIoT platform, Synertrex. “This allows the machines to be monitored remotely; the system can measure the machine’s performance and any deviations arising that may require proactive attention,” he explained.

The order for Nigeria also includes two Trio® jaw crushers, two Trio cone crushers, two large 2 m by 8 m Trio apron feeders, two Trio pan feeders, eight Enduron vibrating screens and an Enduron HPGR.

For the clay washing circuit, Weir Minerals Africa will supply the mine with a Trio twin-shaft blade mill and Trio twin-shaft coarse washers as well as Warman® slurry pumps.

Weir adds aftermarket and service contract to Iron Bridge remit

The Weir Group says it has won a £95 million ($127 million) order to provide aftermarket components and service to the Iron Bridge magnetite project in Western Australia.

The aftermarket contract follows Weir’s success in winning a record £100 million order for original equipment for the Iron Bridge project in 2019, including its Enduron® High Pressure Grinding Rolls (HPGRs, pictured) that, it says, will enable dry processing of ore and use at least 30% less energy than traditional alternatives.

The Iron Bridge magnetite project is a $2.6 billion joint venture between Fortescue Metals Group’s subsidiary FMG Magnetite Pty Ltd and Formosa Steel IB Pty Ltd located in the Pilbara region, around 145 km south of Port Hedland.

Both the aftermarket order and revenues will be recognised over the seven-year period of the agreement, which starts in 2022, in line with the 22 Mt/y project’s initial production.

Ricardo Garib, President of Weir Minerals, said: “This is another landmark order for Weir. Having helped design an energy and water efficient magnetite processing plant, we are delighted to provide operational support for Iron Bridge from 2022. It is an excellent example of the value that Weir’s innovative engineering and close customer support can create for all our stakeholders and reflects the key role we have to play in making mining operations more sustainable and efficient.”

Weir’s Enduron HPGRs are increasingly replacing conventional mills in comminution circuits, Weir says. In addition to their energy and water savings, they also reduce grinding media consumption, while their wearable components last longer, reducing maintenance costs. Additionally, HPGRs contribute significantly to carbon dioxide emission savings.

Stuart Hayton, Managing Director of Weir Minerals Netherlands, where the Enduron HPGRs are designed and manufactured, said: “This is an important project for Weir and for the broader mining industry. We know comminution is one of the most energy intensive parts of the mineral process and, with our Enduron HPGRs, we have a unique ability to offer significant cost, energy and water savings to customers around the world. As the mining industry evolves, we are commited to continuing to innovate, reducing miners’ costs and environmental impact.”

This latest contract award means Weir now has more than £200 million of orders from the Iron Bridge project including its Enduron HPGRs, GEHO® and Warman® pumps, Cavex® hydrocyclones and Isogate® valves.

To support the project and future growth, Weir says it will build a new service centre in Port Hedland, Western Australia, thereby providing employment and training opportunities in the area, with a particular emphasis on supporting greater Aboriginal representation in the broader mining workforce.

New Weir Minerals Sand Wash Plant to boost recoveries

Weir Minerals has released a complete sand wash solution that draws on its long experience in the sand and aggregate industry.

The Weir Minerals Sand Wash Plant comes with Linatex® lining, produces more saleable product than conventional sand screw plants, with fewer moving parts, and has an optimised process that produces a drier, higher-quality product with less fines, according to the company.

The solution has already proven effective at sites like Coimbatore Minerals in Tamil Nadu, India, Weir says, where a custom-built wash plant reduced its total cost of ownership by 51%, while offering a 23% reduction in fines that helped the company consistently meet the industry’s high standards for a saleable product.

Bruce Cooke, Global Product Manager – Sand Wash Plants for Weir, said: “We know the most important thing for quarry operators in washing is recovering as much sand as possible to maximise their sales, which is why we’ve designed an integrated solution for washing their product, with a hydrocyclone which can deliver greater recovery than sand screws. In addition, every component has been selected by our expert engineers for its long-service life, interoperability and ease of maintenance.”

The compact solution features a range of Weir Minerals equipment designed for high efficiency in sand and aggregate applications, including Warman® WGR pumps, Cavex® hydrocyclones, Enduron® dewatering screens, Linatex hoses and Isogate® knife gate valves.

The Warman WGR is a popular pump in the sand extraction industry, according to Weir, combining top of the line hydraulic design with an adjustable impeller, long bearing life and a simplified wet end, making replacement predictable and cost effective.

Precision moulded and lined, Linatex premium rubber is used for wear zones throughout the plant due to its proven wear performance in wet sand applications in operations around the world, Weir said.

Cavex hydrocyclones provide “exceptional classification efficiency” thanks to their unique 360° laminar spiral, delivering more saleable product than a sand screw solution would, the company said. Enduron dewatering screens, meanwhile, reliably separate product with a high degree of efficiency. And, finally, Isogate knife gate valves contribute to the plant’s straightforward maintenance.

Surendra Menon, President, Weir Minerals India, said: “For the new sand wash plant, we focused on making it quick and easy for quarry operators to get up and running. Its straightforward design means it can be assembled in just two days while its compact skids make it easy to drag into any operation.

“Efficient, reliable and easily integrated into flowsheets, we think the plant is a game changer for quarry owners.”

Weir Minerals Africa putting newly designed vibrating screens to the test

Weir Minerals Africa, having over the last 40 years proven the credentials of its Enduron® range of vibrating screens, is now locally designing and manufacturing new-generation linear motion vibrating screens.

One of these new, modern screen designs is part of a recent Weir Minerals Africa complete comminution plant contract for a South Africa mining project. The scope included two crushing stations, a screening station and all the related feed chutes, bins and conveyors.

According to Christian Stehle, Head of Engineering at Weir Minerals Africa, the company’s design capability provides the flexibility to produce vibrating screens to suit each customer’s plant layout. At the same time, the designs will optimise cost, efficiency and performance. South Africa also hosts Weir Minerals’ global screening and separation technology group.

“This expertise ensures that our robust Enduron vibrating screens provide exceptional classification and dewatering screening performance,” Stehle said. The screens are deployed in a wide range of minerals processing applications.

He noted that vibrating equipment is generally more challenging to design than static equipment due to the high frequency cyclic loading to which the machines are subjected.

“The final design must address key criteria like screening efficiency, throughput and loading, while still operating within the acceptable fatigue life limits of the materials of construction,” he said.

Stehle highlighted that the use of finite element analysis (FEA) tools allow engineers to optimise screen life by obtaining the stress and deflection levels in the equipment and applying the appropriate structural design and utilisation of materials in the areas experiencing high stresses.

“Traditionally, screen designs used to be heavier in an effort to extend the life of the equipment,” he said. “Using FEA tools during the design stage allows us to retain structural integrity while actually reducing the overall weight of the machine.”

While there are areas of high stress on the equipment that need more strength, technology tools indicate where lower stresses occur. In these areas, less steel can be used to make the structure lighter, according to Weir Minerals Africa. Leveraging this technology, the weight of some new-generation screens has been cut by up to 15%, the company said.

Stehle noted that Weir’s Synertrex™ IoT platform can also be applied to monitor and improve the performance of the company’s vibrating screens. Synertrex technology is an industrial internet of things system that allows operators to monitor every aspect of their equipment’s operation, to prevent problems and increase throughput.

Weir Minerals gives its skew view on HPGRs

With industry demand for high pressure grinding rolls (HPGR) on the up, Weir Minerals is arguing that skewing is a vital feature for modern HPGRs to reduce wear, save downstream energy and ensure optimal grinding across the whole feed.

The company was sharing its findings following the publication of a new white paper.

Weir said: “With their excellent throughput capacity, low maintenance requirements and energy efficiency, HPGRs are fast becoming a go-to for greenfield projects looking to maintain their margins despite commodity price pressures and declining ore grades.”

The mineral processing company said, in the June quarter, that it had registered strong demand for its Enduron® HPGR technology during the three-month period, later on in the year confirming a major order, which included this comminution equipment, from Fortescue Metals Group for its Iron Bridge magnetite project in Western Australia.

Henning Knapp, HPGR Process Team Leader for Weir Minerals, said the applications from this equipment have evolved from the cement production days of the 1980s and are increasingly being deployed as tertiary and quaternary crushers in mineral comminution circuits, dealing with tougher ores including iron, gold, copper and diamonds.

“As any engineer will tell you, it’s almost impossible to eliminate feed variance and segregation completely. In the past, this has posed a critical challenge for HPGR operators – but dynamic skewing such as that featured in the Enduron HPGR, maintains optimal pressure across the entire feed.”

Traditionally, HPGR manufacturers have shied away from skewing designs, for fear of roller misalignment creating unfavourable load distributions, and preventing the use of flanged guards to reduce the edge effect, the company said. “However, Weir Minerals’ unique roller bearings design allows for skewing alongside effective edge guards, reducing wear and promoting better grinding.”

The downside of static rollers

A HPGR reduces particles by compressing and crushing the feed between two equally sized, parallel rollers rotating in opposite directions, with a small gap between them. This compresses the feed to 80% of its solid density, where the force of the rollers pushes the rocks against each other and exceeds their compressive strength.

“Inter-particle comminution avoids the direct component wear caused by conventional comminution techniques, and applies immense pressure, up to 27,000 kN, across the entire particle size distribution, which creates the higher proportion of fines HPGRs are renowned for,” says Knapp.

However, segregated feeds can result in markedly uneven particle sizes across the width of the feed, creating high, abrasive pressure on one side of the roll and insufficient pressure on the other. It will also produce a coarser product, requiring more work downstream, according to Weir.

“To compensate for the edge effect, a lateral wall or ‘cheek plate’ is deployed on either side to prevent material exiting the gap between the rollers sideways. The closer this is to the rollers, the better – but that has prevented engineers from introducing the flexibility needed to cope with feed segregation,” explains Knapp.

How Enduron HPGRs skew to maintain optimum pressure

To accommodate this uneven pressure Enduron HPGRs use a spring-loaded lateral wall which not only reduces the edge effect (maintaining a gap of as little as 1 mm) but is specifically designed to facilitate roll skew.

As shown above, an uneven feed will lead to high pressure on one side and not enough on the other. Having one roller skew will facilitate larger material at one end while ensuring the smaller particles on the other side receive enough pressure to be ground down: it maintains an even pressure distribution across the entire feed, saving energy and reducing wear, Weir says.

“The degree to which the Enduron HPGRs skew is largely dependent on the width of the roll, with longer rolls skewing about 5 mm for every metre the roll is wide. However, the effect of even small changes can be significant on local pressure peaks,” says Knapp.

“The skewing should be managed by an advanced control system, which steers the rolls to satisfy the desired output pressure. This system also ensures the skew isn’t too great or maintained for too long, which both disrupt the compressive bed.”

In the case of prolonged or excessive skewing, Enduron HPGRs send a signal notifying the supervising control system and operating staff. Prolonged skewing generally is indicative of a disturbance or fault in up-stream facilities, such as low bunker filling, upstream crusher wear, screen deck wear, or conveyor failure, Weir says.

“Where static rolls suffer from differential pressure, creating undesired product, consuming more energy and suffering additional wear, Enduron HPGRs maintain optimum pressure across the entire feed thanks to their skewing, spring-loaded lateral walls,” Weir said.

Knapp concluded: “When dealing with competent mineral feeds in real-world conditions, there’s simply no substitute for the Enduron HPGR’s ability to maximise performance with skewing.”

Weir secures largest-ever individual mining order from Fortescue

The Weir Group says it has been awarded a £100 million ($123 million) order to provide industry-leading energy saving solutions to the Iron Bridge magnetite project, a joint venture between Fortescue Metals Group and Formosa Steel IB.

The order, which includes a range of Weir crushing and pump equipment including Enduron® high pressure grinding rolls (HPGRs) and GEHO® pumps, will reduce energy consumption and wet tailings waste by more than 30% compared with traditional mining technologies, according to the equipment manufacturer.

The Iron Bridge project, 145 km south of Port Hedland in the Pilbara region of Western Australia, is a $2.6 billion investment in premium magnetite iron ore reserves with annual production, when the mine is fully operational, of 22 Mt/y of 67% Fe concentrate. Delivery of the first ore is expected in 2022.

When the mine build was approved back in April, Fortescue CEO, Elizabeth Gaines, said the innovative design for the project, which included the use of a dry crushing and grinding circuit, “will deliver an industry-leading energy efficient operation with globally competitive capital intensity and operating costs”.

A pilot project to verify the Iron Bridge project design involved processing 1 Mt of ore through a full scale HPGR and air classifier, according to Fortescue.

Weir Group Chief Executive Officer, Jon Stanton, said: “We are delighted to have secured this landmark contract, which is Weir’s largest-ever individual mining order.

“Fortescue challenged us to help create one of the most energy and cost-efficient magnetite ore processing facilities in the world. Our engineers have worked relentlessly to design a solution that is truly innovative – delivering significant energy, water and cost savings. This is a great example of working in close partnership with an ambitious customer who shares our passion for using innovative engineering to make mining more productive and sustainable.”

Ricardo Garib, President of the Weir Minerals division, added: “Our team are really enjoying working with Fortescue. Our engineers relish a challenge and it has been great to work on a project that demonstrates the substantial cost and environmental savings that our range of solutions can offer.

“As more mines look to increase productivity, we look forward to even more opportunities to leverage our combination of passionate people, innovative solutions and comprehensive global service capability.”

Weir’s Enduron HPGRs are increasingly replacing conventional mills in comminution (crushing, screening and grinding) circuits because of their substantially lower energy consumption and potential for significant total cost of ownership reduction, Weir says.

“Not only do they require as much as 40% less energy than traditional alternatives, but their wearable components last much longer and the maintenance time required to replace worn out parts is significantly lower.”

The company outlined the reasons why companies are turning to Enduron HPGRs in a blog post earlier this week.

Weir Minerals says Enduron HPGRs crush the competition

Weir Minerals says its range of Enduron® high pressure grinding rolls (HPGR) make for the perfect pebble crushers, offering highly efficient reduction and generating substantial amounts of fines that reduce the energy required for downstream milling.

These units also reduce water and energy consumption, two resources that miners are actively looking at within their operations.

In the company’s June quarter results, Weir noted that it had seen strong demand for its Enduron HPGR technology, adding that the company had been contracted to support a large greenfield development in the UK in the period.

Whether recirculated through primary milling or separated and sent to a dedicated downstream pebble mill, pebble crushing is an energy-intensive operation that ties up a site’s limited resources, Weir says.

“With their high throughput and capacity for dealing with competent ores, HPGRs make ideal pebble crushers,” the company said. The Enduron HPGR’s low operating costs (owing to its long component wear life and low specific energy requirements) makes it a competitive inclusion in pebble crushing circuits, offering short payback times, according to the company.

Ranging in size from 25-90 mm, pebbles are oversized material produced from autogenous and semi-autogenous grinding, which are too coarse to be crushed by larger lumps of ore and steel balls and too fine to act as grinding media themselves.

As such, pebbles (or critical particle size material) reduce the efficiency of any mill they’re returned to, increasing power consumption and decreasing throughput, Weir says.

When pebbles comprise a large proportion of a (S)AG mill’s feed as they’re returned multiple times, the proportion of large particles which have the power to crush with the force of their impact is reduced and new particles are instead subjected to additional attrition and abrasion. “This can over-grind fines, producing unsuitable ultra-fines,” Weir says.

Regardless of whether they’re receiving feed directly from an upstream SAG mill or further reducing pebbles that have passed through a dedicated cone crusher, HPGRs offer highly efficient reduction, generating substantial amounts of fines that reduce the energy required for downstream milling, Weir says.

“The fineness of products is one of the key compromises in conventional pebble circuits, with pebble crushers unable to maintain high throughput without sacrificing the proportion of well reduced particles.”

By virtue of their variable roll speeds, HPGRs can maintain high levels of throughput without generating a coarser product, allowing a significant amount of product to bypass downstream mills via pre-classification, the company explained.

To obtain the greatest efficiency, an appropriate control system should be selected to monitor and maintain the material level in the HPGR feed chute and control the roll speed and apply optimal operating pressure based on the presented pebble feed rate and quality, according to Weir.

One thing to note when deploying a HPGR in a pebble crushing circuit is that truncated feed (one with a narrow size distribution) may cause higher wear on the surface of the machine’s rollers than encountered in other applications. This is due to the more “mobile” particles generating a weaker autogenous wear layer where the coarse pebble fragments chip away at the coating on the roll-surface.

Oversized rocks that are larger than the machine’s operating gap will further wear away at the roller surface, making the use of a safety screen advisable if the preceding crusher’s output isn’t strictly controlled, Weir says.

Similarly, when placed after a (S)AG mill, a significant quantity of oversized or tramp materials can disrupt HPGR operations. “With their unique ability to dynamically skew their bearings to accommodate varying feed conditions, Enduron HPGRs cope better than other HPGRs under these conditions,” the company said.

However, to further reduce damage to wear materials, a well-designed detection and removal system should be applied, Weir advises. “This would consist of a tramp magnetic separator, a metal detector, and a subsequent tramp metal rejection facility. Such a system should preferably be installed as close as possible to the HPGR, preferentially directly ahead of the HPGR feed chute.”

In circuits with particularly heterogenous ore competencies, such as transition gold ores or coarsely-banded iron ores, HPGRs should be run at variable speeds to ensure throughput is maintained regardless of the feed conditions, according to Weir.

The company concluded: “With the ability to maintain this high level of throughput across a variety of ore types without compromising the fineness of their product, Enduron HPGRs represent an ideal, energy-efficient addition to most pebble crushing circuits.”

Weir highlights Enduron HPGR and Terraflow tailings demand in H1 results

The Minerals and ESCO divisions continued to stand out in Weir Group’s half-year 2019 financial results, with the two mining focused segments now representing around 75% of group revenues.

The Weir Group recorded revenue of £1.3 billion ($1.6 billion) in the first six months of the year, up from £1.07 billion a year earlier prior to the ESCO acquisition. Operating profit, meanwhile, was £172 million, up 25% year-on-year, with the Minerals division posting an operating margin of 17.2% and ESCO recording a margin of 14.1% (up 300 basis points from a year earlier).

In addition to Minerals and ESCO now commanding some 75% of group revenues, the two’s recurring aftermarket sales also now represent about 80% of total revenues.

In the first half of 2019, Minerals orders grew 5% with aftermarket orders up 8%, reaching record levels, according to Weir. “Original equipment orders, which are traditionally lumpier, fell by 2% year-on-year, but returned to growth in Q2 (June quarter) and this is expected to accelerate in the second half,” the company said.

ESCO, meanwhile, recorded a 5% increase in pro-forma revenues to £280 million, with annualised cost savings of $20 million ahead of schedule when it comes to the company’s medium-term target of achieving $30 million synergies.

During the period, original equipment demand within the Minerals segment benefited from miners continuing to expand current operations and investment in new mines, with demand for new technologies that increase efficiency and sustainability while lowering total costs, Weir noted.

This included strong demand for the company’s Enduron® HPGR (high pressure grinding roll) technology that reduces water and energy consumption, the company said, adding that the company had been contracted to support a large greenfield development in the UK in the period.

Weir said it also saw growing interest in its Terraflow® solution to enable tailings waste to be cost-effectively recycled or repurposed. This equipment brings wet tailings down to 90% solids paste to be pumped into a containment area or used for paste backfill.

The company added: “Aftermarket demand was strong, due to production growth and structural trends. These include continued ore grade declines that increase the amount of rock that needs to be processed, intensifying wear and tear and leading to additional demand for spares and services,” the company added.

During the period, Weir also added a new Minerals service facility in Alaska, which, it said, gives the division the ability to rapidly respond to demand for spares and services and is a “key differentiator in need-it-now mining markets, where production intensity is increasing, and the costs of unplanned downtime are significant”.

The company’s technology work continued to focus on incremental innovations and “Mine of the Future developments” aimed at solutions that are smarter, more efficient and sustainable, Weir said. This included focusing research and development on new pump and alloy designs, digitisation, ore hoisting, hybrid separation and tailings management.

Weir ESCO benefited from the same macro mining trends as its Minerals segment including increased ore production and the focus by mining customers on optimising productivity, the company said.

“This supported demand for differentiated technology that is proven to sustainably increase efficiency,” it said.
The first half of the year saw early market share gains for the N70 Nemisys® lip system, which extends the division’s Nemisys technology – featuring a cast or plate lip with shrouds and a three-piece tooth system. This is currently being trialled on smaller machine classes including wheel loaders, Weir said. “The N70 improves customer productivity through increased wear life, lower fuel consumption and reduced maintenance costs.”

The company also launched its GET Detect System during the period, an innovation it worked with Australia’s Mining3 on that provides instant feedback to the machine operator if one of the ground engaging tools used to extract minerals is lost or damaged.